(a) Field
Embodiments of the present invention relate to an LED light emitting device and a driving method thereof. More particularly, embodiments relate to an LED light emitting device for controlling a power supply voltage supplied to an LED channel, and a driving method thereof.
(b) Description of the Related Art
An LED light emitting device drives an LED by supplying a current to the LED. The LED emits light with brightness that corresponds to the current. The LED light emitting device emits light with predetermined brightness by controlling a predetermined current to flow to an LED channel configured with a plurality of LEDs coupled in series. An operation for supplying a current to the LED channel and emitting it is called a turn-on operation, and an operation for intercepting supply of current to the LED channel and thereby stopping emission of light is called a turn-off operation.
The LED light emitting device includes a plurality of LED channels, and controls the current flowing to the LED channels. A plurality of LED channels are coupled in parallel, and the power supply voltages applied to the respective LED channels are the same.
When the period in which the LED channel is turned on is short, the operational time of the power supply for generating a power supply voltage is reduced. The power supply voltage is reduced so the power supply voltage is reduced to be less than a voltage level for driving the LED channel. When the power supply voltage is reduced, the LED channel may not be operated or the current supplied to the LED channel is reduced to decrease the light of the LED channel.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.